While the sweeps of the past commonly led to the deportation of such workers, the “silent raids,” as employers call the audits, usually result in the workers being fired, but in many cases they are not deported.

Over the past year, Immigration and Customs Enforcement has conducted audits of employee files at more than 2,900 companies. The agency has levied a record $3 million in civil fines so far this year on businesses that hired unauthorized immigrants, according to official figures.

What do the worlds religious texts and traditionssuggest the authorities do about illegal immigration?

…The audits force businesses to fire every suspected illegal immigrant on the payroll— not just those who happened to be on duty at the time of a raid — and make it much harder to hire other unauthorized workers as replacements.

…“Instead of hundreds of agents going after one company, now one agent can go after hundreds of companies,” said Mark K. Reed, president of Border Management Strategies…

…Employers say the Obama administration is leaving them short of labor for some low-wage work, conducting silent raids but offering no new legal immigrant laborers in occupations, like farm work, that Americans continue to shun despite the recession.

…Immigrant advocates said they are surprised and frustrated with Mr. Obama, after seeing an increase in enforcement activity since he took office. “It would be easier to fight if it was a big raid,” said Pramila Jayapal, executive director of OneAmerica, a group in Seattle. “But this is happening everywhere and often.”